[v3,0/7] Support GEM object mappings from I/O memory

Message

Thomas Zimmermann Sept. 29, 2020, 3:14 p.m. UTC

DRM's fbdev console uses regular load and store operations to update
framebuffer memory. The bochs driver on sparc64 requires the use of
I/O-specific load and store operations. We have a workaround, but need
a long-term solution to the problem.

This patchset changes GEM's vmap/vunmap interfaces to forward pointers
of type struct dma_buf_map and updates the generic fbdev emulation to
use them correctly. This enables I/O-memory operations on all framebuffers
that require and support them.

Patches #1 and #2 prepare VRAM helpers and TTM for the changes in patch
#3. Patch #3 updates GEM's vmap/vunmap callback to forward instances of
type struct dma_buf_map. While the patch touches many files throughout the
DRM modules, the applied changes are mostly trivial interface fixes.

Patch #4 updates GEM's internal vmap/vunmap functions to forward struct
dma_buf_map.

Patches #5 and #6 convert DRM clients and generic fbdev emulation to use
struct dma_buf_map. Updating the fbdev framebuffer will select the correct
functions, either for system or I/O memory.

The patch set is just enough to fix the bochs issue on sparc64 and a
correct way. Patch #7 updates the TODO list with ideas for further
improvements

v3:
	* recreate the whole patchset on top of struct dma_buf_map

v2:
	* RFC patchset

Thomas Zimmermann (7):
  drm/vram-helper: Remove invariant parameters from internal kmap
    function
  drm/ttm: Add ttm_kmap_obj_to_dma_buf_map() for type conversion
  drm/gem: Use struct dma_buf_map in GEM vmap ops and convert GEM
    backends
  drm/gem: Update internal GEM vmap/vunmap interfaces to use struct
    dma_buf_map
  drm/gem: Store client buffer mappings as struct dma_buf_map
  drm/fb_helper: Support framebuffers in I/O memory
  drm/todo: Update entries around struct dma_buf_map

 Documentation/gpu/todo.rst                  |  24 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.c |  14 +-
 drivers/gpu/drm/amd/amdgpu/amdgpu_dma_buf.h |   4 +-
 drivers/gpu/drm/ast/ast_cursor.c            |  29 ++-
 drivers/gpu/drm/ast/ast_drv.h               |   7 +-
 drivers/gpu/drm/bochs/bochs_kms.c           |   1 -
 drivers/gpu/drm/drm_client.c                |  38 ++--
 drivers/gpu/drm/drm_fb_helper.c             | 238 ++++++++++++++++++--
 drivers/gpu/drm/drm_gem.c                   |  28 ++-
 drivers/gpu/drm/drm_gem_cma_helper.c        |  14 +-
 drivers/gpu/drm/drm_gem_shmem_helper.c      |  48 ++--
 drivers/gpu/drm/drm_gem_vram_helper.c       |  93 ++++----
 drivers/gpu/drm/drm_internal.h              |   5 +-
 drivers/gpu/drm/drm_prime.c                 |  14 +-
 drivers/gpu/drm/etnaviv/etnaviv_drv.h       |   4 +-
 drivers/gpu/drm/etnaviv/etnaviv_gem_prime.c |  11 +-
 drivers/gpu/drm/exynos/exynos_drm_gem.c     |   6 +-
 drivers/gpu/drm/exynos/exynos_drm_gem.h     |   4 +-
 drivers/gpu/drm/lima/lima_gem.c             |   6 +-
 drivers/gpu/drm/lima/lima_sched.c           |  11 +-
 drivers/gpu/drm/mgag200/mgag200_mode.c      |  12 +-
 drivers/gpu/drm/nouveau/nouveau_gem.h       |   4 +-
 drivers/gpu/drm/nouveau/nouveau_prime.c     |   9 +-
 drivers/gpu/drm/panfrost/panfrost_perfcnt.c |  14 +-
 drivers/gpu/drm/qxl/qxl_display.c           |  13 +-
 drivers/gpu/drm/qxl/qxl_draw.c              |  16 +-
 drivers/gpu/drm/qxl/qxl_drv.h               |   8 +-
 drivers/gpu/drm/qxl/qxl_object.c            |  23 +-
 drivers/gpu/drm/qxl/qxl_object.h            |   2 +-
 drivers/gpu/drm/qxl/qxl_prime.c             |  12 +-
 drivers/gpu/drm/radeon/radeon_gem.c         |   4 +-
 drivers/gpu/drm/radeon/radeon_prime.c       |   9 +-
 drivers/gpu/drm/rockchip/rockchip_drm_gem.c |  22 +-
 drivers/gpu/drm/rockchip/rockchip_drm_gem.h |   4 +-
 drivers/gpu/drm/tiny/cirrus.c               |  10 +-
 drivers/gpu/drm/tiny/gm12u320.c             |  10 +-
 drivers/gpu/drm/udl/udl_modeset.c           |   8 +-
 drivers/gpu/drm/vboxvideo/vbox_mode.c       |  11 +-
 drivers/gpu/drm/vc4/vc4_bo.c                |   6 +-
 drivers/gpu/drm/vc4/vc4_drv.h               |   2 +-
 drivers/gpu/drm/vgem/vgem_drv.c             |  16 +-
 drivers/gpu/drm/xen/xen_drm_front_gem.c     |  18 +-
 drivers/gpu/drm/xen/xen_drm_front_gem.h     |   6 +-
 include/drm/drm_client.h                    |   7 +-
 include/drm/drm_gem.h                       |   5 +-
 include/drm/drm_gem_cma_helper.h            |   4 +-
 include/drm/drm_gem_shmem_helper.h          |   4 +-
 include/drm/drm_gem_vram_helper.h           |   4 +-
 include/drm/drm_mode_config.h               |  12 -
 include/drm/ttm/ttm_bo_api.h                |  24 ++
 include/linux/dma-buf-map.h                 |  92 +++++++-
 51 files changed, 685 insertions(+), 305 deletions(-)

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2.28.0